Method and apparatus for continuous horizontal casting



Nov. 1, 1966 w. c. ROSS 3,281,903

METHOD AND APPARATUS FOR CONTINUOUS HORIZONTALCASTING Filed Feb. 3, 1964 4 Sheets-Sheet 1 INVENTOR. Wa/fer 6. Ross HIS ATTORNEYS LO N BZULQOS W. G. ROSS Nov. 1, 1966 METHOD AND APPARATUS FOR CONTINUOUS HORIZONTAL CASTING 4 Sheets-Sheet 2 Filed Feb. 5, 1964 o INVENTOR.

Walter 6. Ross 5% HIS ATTORNEYS Nov. 1, w. c. ROSS METHOD AND APPARATUS FOR CONTINUOUS HORIZONTAL CASTING Filed Feb. 5, 1964 4 Sheets-Sheet 5 I r50 ;6 7? 7s 73 M r i2 I 5 M II III I! llilli gigging" INVENTOR War/fer 6. Ross lax/ Q77: @MwM H/S ATTORNEYS Nov. 1, 1966 w. c. ROSS 3,2L903 METHOD AND APPARATUS FOR CONTINUOUS HORIZONTAL CASTING Filed Feb. 5, 1964 4 Sheets-Sheet 4 I .48 II" INVENTOR Wa/ier 6. Ross H/S ATTORNEYS United States Patent 3,2813% METHGD AND APPARATUS FUR CONTINUOUS HORIZONTAL CASTING Walter C. Ross, 1789 Hastings Mill Road, Rridgeville, Pa. Filed Feb. 3, I964, Ser. No. 341,957 13 Claims. (tCl. 2257.3)

This invention pertains to improved procedure and apparatus for progressively forming a continuous metal casting, such as a slab, plate or bar, and more particularly to procedure and apparatus for forming a continuous length of cast metal within a horizontal chamber directly from molten metal' At the present time, the direct casting of metal shapes has been successfully accomplished by overhead vertical means, but such an operation is wasteful of plant space and for a continuous length necessitates bending and stretching the casting in order to utilize and process it. The present invention deals with the problem of providing a practical production type of operation for directly forming a cast metal length horizontally, as by the utilization of molten metal supplied from a furnace ladle.

One approach to the problem of providing a horizontally-formed casting has been to individually cast lengths of the metal by intermittently filling endwise-positioned connected molds with molten metal in a surrounding gaseous atmosphere, and utilizing an apron to consolidate the metal on the molds. Thereafter, additional molds are presented and the operation is continued in a step-by-step manner. This procedure produces a relatively poor quality of casting due to contamination and due to unevenness of the cooling operation. Further, it is an expensive procedure and limits the length of casting which is produced.

Another horizontal casting approach involves the utilidation of cooperating upper and lower, continuouslymoving belts, with means carried by one of the belts for collecting the molten metal and advancing forwardly as it is solidified. To facilitate solidification and to protect the belts, water is sprayed directly on the molten metal and the casting as it is being formed. This also produces a poor quality of metal, in that it is subjected to both contamination from atmospheric gases and moisture, requires a rather complex apparatus arrangement, and is impositive in the feed of the molten metal.

In both of the above described approaches, difiiculty has also been encountered in attempting to strip the metal casting, as formed, without distorting or bending it out of shape.

I have been able to devise an economical and practical procedure for producing metal castings, such as slabs, plates or bars of continuous infinite length and of high quality that may be directly used as cast or further proc essed in accordance with conventional procedures. I have been able to accomplish these results in a practical manner by meeting the adverse factors of prior art constructions and particularly, by enabling the progressive forming of a continuous metal length by effectively utilizing the weight of the molten metal in accomplishing an improved type of feeding operation, by eliminating moisture and gas contamination (such as represented by the am bient atmosphere or a direct application of cooling fluid), by utilizing an enclosed or sealed-off horizontal mold chamber to which temperature controlling fluid is indirectly applied in forming the casting, by utilizing a top side or upper wall of the mold chamber for controlling the desired thickness of the metal casting and further, by controlling the stripping of the formed casting in such a manner that the horizontal cast metal length, as progressively produced, can be continuously fed forwardly without distorting or bending it.

It has thus been an object of my invention to devise new and improved procedure for casting molten metal and particularly, for providing a continuous horizontal length of the cast meta-l of a desired thickness and high quality;

Another object of my invention has been to develop a new concept in the art of casting molten metal and particularly, from the standpoint of continuously casting molten metal on a substantially horizontal plane;

Another object of my invention has been to develop an apparatus arrangement or system which will enable the carrying out of my new procedure as based upon my concept;

A further object of my invention has been to make possible the handling of the molten metal in a sealed-oif relation with respect to the atmosphere from the time it leaves a ladle or other source until it is formed and, in such a manner that it will have a protective skin, at least on its subsequently exposed upper side when, during its progressive advance, it leaves the mold chamber and is exposed to the ambient atmosphere;

A further object of my invention has been to provide a flexible procedure and means for forming a continuous metal length or slab of high quality and of a desired thickness which may be subsequently cut-off into desired lengths and may be slit into desired widths during its continuous forward movement;

These and other objects of my invention will appear to those skilled in the art from the illustrated embodiments, the description thereof and the claims.

In the drawings, FIGURE 1 is a longitudinal side view in elevation of a longitudinal system or apparatus arrangement constructed and employed in accordance with my invention;

FIGURE 2 is a top plan view on the same scale as and of the system of FIGURE 1;

FIGURE 2A is a fragmental top plan view on the scale of FIGURE 2 showing a modified apparatus arrangement;

FIGURE 3 is an enlarged side elevation, partially in section, showing details of the construction of a casting unit of my invention and represented by the left-hand portion of the system of FIGURES l and 2;

FIGURE 4 is an end section in elevation on the scale of FIGURE 3 and taken along line IVIV of FIG- URE 5;

FIGURE 4A is a fragmental top plan view on the scale of FIGURES 3 and 4 showing details of a pivot joint or connection between mold parts;

FIGURE 5 is a fragmental side in elevation on the scale of FIGURES 3 and 4, showing details of the construction of a front end portion of molding conveying apparatus of FIGURES l and 2;

FIGURE 6 is a fragmental side view in elevation on the scale of FIGURES 3 and 4, showing details of an exit or back end portion of the mold conveying apparatus of FIGURES l and 2;

FIGURE 7 is a partial end or transverse section in elevation on the scale of and taken along the line VIIVII of FIGURE 6;

FIGURE 8 is a fragmental side view in elevation and partial section on the scale of FIGURE 3, showing a detail of the construction of a connector spout in its maximum outward or upward position in readiness for is on the same scale as and is shown in FIGURE 3 in its up position of utilization;

FIGURE 11 is a traverse or end view in partial section on the scale of and taken along the line XI-XI of FIG- URE And, FIGURE 12 is a schematic view of a circuit diagram suitable for use in the operation of the apparatus of FIGURE 3.

Referring particularly to FIGURES 1 and 2 of the drawings, I have illustrated a system or longitudinal processing line or layout constructed in accordance with my invention which employs a conventional molten metal or molten steel handling ladle A, a casting unit B of my invention, a casting mold assembly or continuous mold assembly C of my invention which is adapted to be moved in a continuous path that is horizontal along its upper and lower reaches and that is somewhat elliptical at its opposite ends, a guide track system or arrangement D for the mold assembly, and a back or exit end positively-driven roller conveyor table or unit E which may correspond to a rolling mill runout table provided with gear motors for its rollers and which receives a cast slab from the mold assembly C and advances its length forwardly without in any sense distorting or bending the casting. In addition, I have illustrated a conventional shearing or cut-off unit F which may be used for cutting-off end crop from the cast metal slab and for cutting the continuous length of casting into any suitable desired length of slab, and a gang slitting saw unit G for sawing the cut-off length of metal slab into individual lengths of a desired width. Also, in FIGURES l and 2, unit H represents a transfer table for receiving the cut-off lengths of cast metal slab, and I represents a transfer table conveying extension for moving the cut-off length transversely of the longitudinal production line, in order that they may be taken-off and piled or further processed in the shop.

In FIGURE 2A, there is shown an alternate processing line arrangement in accordance with which a continuous length of casting may be directly introduced from the driven conveyor table E through a hot rolling mill and then, if desired, through suitable cold rolling, shaping or reducing mills. Of course, it will be appreciated by those skilled in the art that the continuous slab, as utilized in accordance wit-h FIGURE 2A, may be sheared as to its length before the rolling operation and also sheared into suitable widths or lengths, before or after the roll passes as desired, empolying units such as F and G.

In FIGURES 1 and 2, I have further diagrammatically illustrated a cleaning unit K which may be of any conventional spray, brush or sand blasting type, and which is utilized for progressively cleaning individual molds during their return or under movement. Heat applicator units, such as L and L may be used for bringing the molds up to a suitable temperature. In this connection,

- one or both of the units L or L may be used; if both are used, L may be employed to preliminarily bring the molds up to a suitable temperature corresponding to a coating temperature, and L may be used to progressively bring the molds up to a final temperature for fixing the coating and for providing the molds with a suitable temperature for the casting operation. The units L and L may use conventional electrical or gas heating units with a blower for concentrating the heat as the molds move past the stations. Station N illustrates a spray unit for the application of a suitable coating slurry to the inside of the molds during their return or under movement. Such a slurry may be of conventional type such as a mixture of graphite dust in molasses.

Referring also to FIGURE 3 of the drawings, it will be apparent that, in accordance with my invention, molten metal, such as supplied by a ladle A or other suitable source, is fed as by means of a ladle stopper 13 in a controlled manner and in a sealed-off relation from the standpoint of the surrounding or ambient atmosphere, by means of a connector spout 30, directly into a tundish chamber of a casting and metal supply unit B of my invention. Molten metal which is received in the tundish chamber is fed downwardly forwardly in an inclined plane through a feed orifice into a horizontal casting chamber that is defined as to its one end by the back wall of a feed orifice of the tundish chamber, a shown in FIGURE 3. The horizontal casting chamber is initially closed-off at its opposite or exit end by an end closure gate 48 and subsequently, as shown in FIGURE 3, by the cross-section of a solidifying portion of the metal length. The casting chamber is defined along its major or horizontal extent by a series of closely endwise-abut ting, open-top and aligned open-end molds or mold parts whose bottom and upright, opposed, side portions provide a continuous channel-shaped wall, and also on its opposite or upper side by an adjustable top gate or upper wall 40. It will be noted that the gate 40 is provided with means 41 in the nature of jacketing or embedded fiuid piping for controlling the temperature of such gate or wall 40 as well a the casting temperature of the metal 61 being formed or solidified into a slab. Importantly, the gate 40 provides a mold side or top wall which cooperates with and provides a top closure wall for the molds 70 to define a horizontal mold chamber with the molds 70 and to control the thickness of the cast metal 61 which is being formed.

In accordance with my procedure, the molten metal is solidly and smoothly cast as a continuous length within the horizontal casting chamber. This is assured by utilizing the weight of the molten metal in the tundish in supplying the molten metal inrequisite quantity to the horizontal mold chamber. In this connection, it will be noted that, initially, in starting up the operation, the swing end gate 48 may be closed (see FIGURE 10) until the mold chamber is filled with metal and the wall or gate 40 has been properly adjusted from the standpoint of a desired thickness of the casting and its temperature adjusted by a flow of cooling fluid therethrough. The cast metal or ingot is provided with a protective skin, particularly along its upper side that is initially exposed when the ingot leaves the exit or forward end of the chamber (see FIGURE 3). The utilization of a molten metal collecting tundish chamber and the forward-downwardly inclined positioning of the feed orifice therefrom gives an unexpected result of enabling the casting rate to be varied within a relatively wide range of speed as to the molds 70, without adversely affecting the quality of the cast ingot. I have found that the forward advancing movement of the molds tends to further this desirable result, in the sense that the molten metal is pulled forwardly along the molds as they advance from the feed orifice of the tundish and into and along the mold chamber. In this connection, I have found that a forward operating movement of the molds 70 at a rate of about five to fifty feet per minute can be accomplished to produce a continuous length of a good quality metal slab, utilizing the apparatus illustrated particularly in FIGURE 3 of the drawings. The forward speed of the molds 70 is determined by the thickness of the slab being formed. For example, a slab of four inches in thickness may be moved at arate of about ten feet per minute.

Also, as illustrated in FIGURE 3, the tundish chamber is, and if desired, the control chamber for the wall or gate 40 may be supplied with an inert gas, such as argon, as by a tank 56 so as to seal such chambers off from and prevent the undesirable entry of moisture and contaminating atmospheric gases. An important feature of my invention is the utilization of an inert gas curtain, as accomplished by supplying the inert gas under positive pressure about the feed orifice or about the slight clearance opening of the joint between the feed orifice and the molds 70, and the further utilization of the inert gas as pressure-applied, both to the tundish chamber and about or along the outer bounding area of the feed orifice to prevent the entry of and force out any contaminating gases in the molten metal and particularly, from the molten metal within the casting chamber.

A control and shut-off valve V for the inert gas may be utilized to further control the rate of feed of the molten metal, in combination with the forward-advancing movement of the molds 70 and the gravity action of the molten metal as being fed through the orifice of the tundish chamber. In starting-up the casting operation, warm fluid or water may be passed through the jacketing 41 from a fluid or water supply and control unit 44 to prevent damage to the metal and provide the gate 40 with a suitable initial heat before the heat of the molten metal is conducted thereto. Subsequently, after a length of casting has been formed within the horizontal chamber and the slab thus-formed is advanced forwardlyendwise out of the chamber, then the unit 44 may be shifted to supply cooling fluid to the gate or wall 40 to remove heat from the molten metal in the mold chamber at a requisite rate for casting it and providing it with a protective skin.

The slab, as progressively formed by the addition of molten metal increments to its back end within the casting chamber and the casting of such increments integrally thereon, is formed on a horizontal plane and is advanced and stripped on such a plane off the molds 70 and upon a guide member 79 of the roller conveyor table E in such a manner as to avoid bending such advancing end of the ingot 61 off its horizontal axis or in any way distorting it. In this connection, as shown in FIGURE 6, the ingot is carried forwardly by one side of the mold chamber, as represented by the continuous molds 70, which more it outwardly with respect to the opposed side, as represented by the gate 40 and then, strip it at a forward point at which the ingot 61 has reached a substantially solid state and cannot be easily distorted. The molds 79 move for a distance represented by f of FIGURE 6 on a slight forwardly-declining plane, in the neighborhood of 2 to 3 from the horizontal (see angle e), at which time, the slab is stripped therefrom. After the stripping has been effected, then the molds are moved at an abrupt angle in their end turning movement along the track system D.

Since it is important to continuously form the slab without any breaks or defects therein and without introducing strains in the metal by reason of the movement of the molds 70, I provide means for maintaining the molds in a tight, endwise-abutting, and aligned relation, particularly during the period in which the metal is being cast in the mold chamber. In this connection, the molds 70 are in effect, linked or pivotally interconnected by knuckle joints which, as shown particularly in FIG- URES 4 and 4A, serve also to journal axle shafts 71 on which flanged wheels 73 are carried for movement along flanged track members 68. The molds along at least one side are shown provided with outwardly-projecting teeth 74 which are engaged by a front main driving sprocket wheel 75 and a back secondary driving sprocket wheel 85. It will be noted that the sprocket 85 is located beyond the exit end of the unit B and that the sprocket 75 is located ahead of the entry end of the unit.

During the initial forming of a cast metal length within the mold at the starting-up of the operation, sprocket wheel 75 may be actuated at a slow speed forwardly or clockwise of FIGURE 5, while the sprocket wheel 0'5 may be non-driven, so as to provide a drag against forward movement of the molds 70 through the agency of the sprocket wheel 75 and its connections to its motor M Thereafter, when the end gate 48 has been moved to the upper position of FIGURE 3, a switch S may be actuated to start the back motor M and drive it at a slightly slower speed than the front motor M in order that the sprocket 85 will maintain a slight drag and thus,

assure endwise-abutment of the somewhat loosely connected molds during their movement along the upper horizontal portion of the track system D.

I prefer to employ about one sixteenth of an inch clearance of the shafts 71 about their journals, so as to eliminate any possibility of binding under heat expansion and to, at the same time, permit some slight endwise movement between the molds to assure their tight, endwise-abutment or engagement during the upper portion of their travel and conversely, to provide them with some separation during the lower portion of their travel, as also accomplished by the above described method of operation. The separation is desirable during the lower portion of travel to facilitate cleaning them, heating and coating them prior to their return to a casting position.

If, for example, the molds 70 of channel cross-section have a distance between their upright side walls such as to form a sixty inch width of cast slab or metal length, then the slitting unit G can be utilized to provide various widths of castings or slabs or billets of, for example, six inches through thirty-six inches, more or less. In other words, this provides a method of slicing the slab longitudinally to suit the particular needs of a particular customers immediate requirements. There is thus full flexibility in the utilization of my procedure and system. Incidently, I have found that about three or four feet of forward movement of the ingot 61 beyond the horizontal mold chamber provides it with suflicient solidification for the stripping operation, illustrated in FIGURE 6. By limiting the angle of the stripping operation, I provide sufficient support for the slab 61 until it reaches an entry guide tongue 79 and the first driven roll of the table E so as to avoid bending it.

In FIGURE 3, the ladle A which may be of a conventional type, is shown provided with a pair of outwardly- .projecting trunnions 10 to receive conventional cradle hooks 12 of an overhead traveling shop crane, so that it can be moved from beneath a pouring position with respect to a furnace to a delivery position, such as shown in FIGURE 3. The ladle A, however, is provided with circumferentially spaced outwardly-projecting wings or fins for carrying it on a surrounding rim or flange of a supporting stand 2%). The supporting stand is carried by structural frame members 21 and 21a which are part of the structural frame-work used for carrying and supporting the metal casting unit B. The ladle A is also shown provided with a refractory stopper 13 for closing off the feed opening in its bottom and for controlling the flow of molten metal therefrom. This stopper is, of course, closed when the ladle is being filled adjacent the furnace and when it is being moved by an overhead crane to the supported position of FIGURE 3.

The stopper 13 which may be conventionally of refractory material, and is shown carried by a metal supporting rod 14, an overhead cross arm 15, and a piston rod 16 of a cylindrical, reciprocating, fluid-motor 17. A support bracket 18 projects from the ladle for positioning the motor 17. The motor 17 may be actuated by a fluid, such as air or a liquid. A positive pressure supply line 19a and a return flow line 1% are shown in FIGURE 3 as connected to the valve V The valve V is also shown connected to opposite ends of the motor 17 by lines 17a and 17b. By operating the control valve V a positive flow of fluid from the line 19a may be alternately directed through lines 17a and 17b, and an exhaust or return flow may conversely be directed through lines 17b and 17a to the line 19b. In this connection, I have shown a conventional arrangement of stopper operating mechanism merely for the purpose of illustration.

The casting unit B has a metal top closure plate 23, a metal outside, back plate member 24 which is secured to and projects, first directly-horizontally downwardly from the top plate member 23, and then projects forwardly-downwardly towards the casting mold assembly C. The back plate member 24 is in an outwardly-spaced relation with an inner and opposed metal plate member of similar shape. The member 25 has a series of spacedapart, vertically-extending ribs 25a that reinforce the inner plate member 25, abut the inside of the outer plate member 24, and define a series of downwardly-extending fluid passageways a for a flow of inert gas therebetween. An inner, reinforcing top metal plate member 27 cooperates with the top closure member 23 and provides the top of the tundish chamber; it carries a refractory roof 28 which cooperates with a refractory lining 26 of the wall plate member 25 and a refractory front wall that is carried by a front vertical metal closure plate member 36 to define the tundish chamber.

It will be noted that the plate member 36 defines a partition or separating wall between the tundish chamber and a control chamber for the adjustable wall or gate 40. Metal is introduced into the tundish chamber through a refractory connector spout 30 that extends vertically-upwardly-centrally through the top wall members 23, 27 and the refractory roof 28. The connector spout 30 is slidable at its cylindrinal lower end portion therewithin and is carried by metal positioning ring 31 which rests on an upper collar portion 28a of the refractory roof 28.

As shown particularly in FIGURES 3 and 8, connector spout 30 has an upper, outwardly-projecting, seating flange portion 30a which is adapted to provide a tightly-abutting sealing fit with the bottom of the ladle A in alignment with its feed opening. A spiral tension spring 32 at its lower end rests on the ring 31 and at its upper end abuts against the flange 30a to, as shown in FIGURE 8, normally urge the connector spout 30 upwardly, as limited by cooperating stop fingers 33 and 34. One stop finger 33 is carried by the connector and the other 34 is carried by the top plate member 23. When the ladle is lowered to the position of FIGURE 3, then its weight compresses the spring 32 so as to provide a resilient sealing fit between the seating flange 30a and the bottom of the ladle and thus seal-off the connection from the ambient atmosphere and its contaminating gases, such as hydrogen and oxygen.

As mentioned above, the casting unit B has a control chamber; it is defined by a top metal closure member 35 which projects downwardly from the overall plate cover member 23 and is secured thereto. A metal side wall member 38 extends from the front of the chamber along its sides and is connected to the back plate member 36 to fully enclose the control chamber. The wall assembly 36 and 38 is of rounded or cylindrical construction to adjustably or vertically-slidably position the gate 40 to project downwardly from its open bottom end. The gate 40 is of refractory construction of channel cross-section and is adapted to slide vertically within the Walls 36 and 38 .to control the thickness of the molten metal that flows into the mold chamber, as defined on its upper side by the gate. This gate 40 is also used to control solidification in forming the metal casting or ingot. Fluid jacketing or a piping system 41 is embedded in the gate 40 and is connected through flexible lines 42 and 43 to a fluid supply and fluid temperature controlling unit 44. A U-shaped metal support member 45 carries the refract-ory gate 40 and has a central boss 45a which is provided with a bore to which a lower end of a threaded jack stem or screw 46 is secured by split ring means 46a. The jack stem 46 is part of a conventional fluid-motor-actuated jack screw unit 47 that is used for raising and lowering the gate. In this connection, a Duif-Norton unit has been found to be satisfactory. The casting unit B which is principally carried by the structural framework 21a, also carries the jack screw unit 47 in a mounted relation on the top plate member 35 of the control chamber. The gate 45 may also be used to apply some concentration of pressure on the slab being formed by providing its mold face with a slight upwardly-diverging angle to the horizontal towards the exit end of the unit B, for example, about 1. It will be noted that the metal will tend to shrink downwardly away from the exit end portion of the gate wall or top side 40 during its solidification, thus automatically freeing the slab and minimizing frictional resistance as it moves out of the unit B.

An end swing gate, stopper or closure 48 is mounted on a swing shaft 50 that is carried by a side mount 51. The mount 51 projects from a back portion of the side enclosing wall member 38. The swing gate 48 is provided with a refractory nose portion 49 which is the portion (shown in FIGURE 10) that is moved into direct contact with the molten metal being initially cast in the mold chamber when the gate 48 is in its down position. The mount 51 (see FIGURE 11) has a pair of spaced-apart support lugs that project from the wall 38 and that have bearings for journaling the swing shift 50. As shown particulanly in FIGURE 11, the swing gate or end closure 48 has a pair of arms 48a that are secured on the shaft 50 which extends transversely at one end and it is connected to a reversible motor 53 through a coupling 52. The motor 53 may be a rotary type of fluid drive, reversible motor, such as represented by the Ex-Cell-O Model RN/ROTAC 84-IV unit, illustrated in its Catalog No. 26,282, or any other suitable type of reversible mot-or. The motor 53 is mounted on a support table or stand 54 that is carried by an extension of the frame structure 21a.

Referring again to FIGURE 3, inert gas is shown provided by means of a supply tank 56 within which it is carried under pressure and which has conventional nipple and shut-off valve unit 56a and an outlet connection 57 leading therefrom. Branch lines 58 and 59 lead from the connection 57 through control and shut-off valves V and V respectively, to a connector 58a of the tundish chamber and to a connector 59a of the control chamber. It will be noted that the gas from the line 58 is directly introduced into back-passagewaydefining or spaced wall members 24 and 25 of the tundish chamber and flows along passageways a of such chamber downwardly to a clearance or slide joint spacing c between the bottom of the feed orifice of the tundish chamber and the molds 70, so as to provide an inert gas curtain at the joint and exclude moisture and contaminating gases from the molten metal being introduced into the mold or casting chamber. A passageway b through the wall member 25 and refract-ory wall 26 introduces the inert gas directly into the tundish chamber to force out any contaminating gases through outlet 58b and prevent their entry. Inert gas from the line 59 enters the control chamber above the adjustable side wall or gate 40 through passageway d and prevents the entry of ambient gases along the outside portion of the adjustable slide mounting of the gate 40.

The molten metal is indicated in FIGURE 3 as 60 and the cast metal as 61. Referring to FIGURES 1 and 2, sheared-off lengths of the continuous length of cast metal are indicated as 62, and slit lengths are indicated as 63. The lengths 63 are moved forwardly by the driving movement of the rollers of the conventional roller table E upon the transfer table H and against the front stop 64 from which they may be advanced sidewise by conveyors projecting from the conveyor transfer table unit I to the transfer table H.

The track system D for the mold assembly C is, as shown in representative FIGURES 3, 4 and 5, carried or supported by structural framework 65 and has a pair of side-projecting tables 66 and 67 therealong for carrying drive motors M and M see FIGURES 4 and 7. The frame 65, as also shown particularly in FIGURES 4 and 7, carries transverse members 65a which are in a spaced relation longitudinally therealong and which, in turn, carry a pair of continuous loop-like transversely spacedapart flanged track members or rails 68. As shown particularly in FIGURES 1, 3, 5 and 6, the track members 68 are continuous, in that they extend along both the upper and lower horizontal flight or reach portions of the track system D, as well as along its looped ends. However, to retain the connected, continuous mold system C in position during its under as well as its end turning movement, I have provided a pair of supplemental track or rail members 69 which are also carried on transverse members of the structural frame 65 to cooperate with opposite portions of the flanged wheels 73 of the molds 70. It is thus apparent that the molds 70 are, during the upper portion of their travel, held in position on the track member 68 by their weight and the weight of the metal, and during the under portion of their travel, by their positioning between the opposed pairs of track rail members 63 and 69.

The molds 70, as shown in the various figures and as previously pointed out, are of somewhat cart-like or chain-link construction in their assembly and utilization, and have a bottom or table portion that extends longitudinally therealong and is closed-off along its side by vertically, upwardly-extending opposed side wall portions 76a and 70b to define a suitable depth of mold chamber. The particular depth of mold chamber, such as illustrated in FIGURE 4, is only representative. The portion of the mold chamber defined by each mold 7t is closed-off on its opposite main or upper side by the adjustable gate or wall 40 whose width or transverse extent is such as to provide a close sliding fit between the side walls 70a and 70b (see FIGURE 11). As shown particularly in FIGURES 4 and 4A, one end of each mold 76 has a pair of downwardly and longitudinally-outwardly projecting bearing lugs 70c, and at its other or opposite end, has a pair of downwardly and longitudinally and outwardlyprojecting bearing lugs 700. which provide an :interfitti-ng complementary relationship as between the forward end of one mold and the back end of an adjacent mold. In this manner, the molds 70 are connected together in a pivotal or swingable relation by the knuckles or finger joints defined by the lugs 70c and 70d, in combination with the axle shafts 71.

With reference to FIGURES 4 and 5, the system or assembly C of pivotally-connected casting molds 70 is driven at the front or entry end of the apparatus B by means of a drive sprocket 75 whose teeth 75a engage with the projecting teeth 74 along one side wall 701) of the molds. The sprocket 75 which is the main, positive, forward drive sprocket is keyed to a drive shaft 76 that is carried by stands 77 on the side table 66. The shaft 76 is shown driven by a direct current electric motor M through a conventional coupling 78. In like manner, the back or exit end of the horizontal flight of the casting mold system C is provided with a driving sprocket 85 whose teeth 85a also mesh with the teeth 74. The sprocket 85 (see FIGURES 6 and 7) is keyed on the end of a drive shaft 86 that is carried within stands 87 on the table 67, and that is driven through a coupling 88 and a torsion slip clutch 89 by a direct current electric motor M FIGURE 12 shows a suitable electric circuit diagram for the operation of the motors M and M In this connection, when the casting operation is being started, the switch S may be closed and the rheostat R adjusted to actuate the motor M at a relatively slow speed. At this time, the switch S may be open, so that the motor M will drag and thus produce an endwise closing-up and close abutting relationship of the molds '70 that are positioned between the sprockets 75 and 85 along the upper horizontal flight or reach of the casting mold assembly or system C. At this time, the end gate or closure 48 is in its closed position of FIGURE 10. Molten metal is then introduced into the horizontal chamber by opening the ladle stopper 13 so as to supply the tundish chamber. Fluid temperature control and supply unit 44 which may be a commercial type of unit, will supply fluid, such as water at any suitable temperature; it may be first operated before the molten metal is introduced into the mold chamber to heat the adjustable top wall or gate 40 to a suitable initial temperature.

After the molten metal has been introduced into the mold chamber and the casting operation is started, the unit 44 may be employed to supply cooling fluid to the gate or top wall 40 so as to initiate the solidification of the ingot 61 and assure a protective top skin along the top wall 40. Then, the end gate or closure 48 may be swung upwardly to the position of FIGURE 3, at which time, it will engage micro-switch S to close the electrical circuit to the motor M and cause its forward actuation. The relative speeds of the motors M and M may be adjusted by the rheostats R and R to cause the motor M to drag slightly or move at a slightly slower speed than the motor M thus maintaining the molds 70 in their tight, endwise-abutting relation during the full movement of the mold assembly C along the upper horizontal flight or reach of the system. This type of actuation also assures that the molds 70, during their movement along the bottom or return horizontal flight, are pulled slightly away from each other so as to facilitate their cleaning, coating, etc. Incidentally, any suitable cleaning type of operation may be accomplished by means of the unit K of FIGURES l and 2, including sand blasting and brushing operations. The motor M is provided with a slip clutch 89 which is set to provide a suitable torsion resistance to further the endWise-abutting movement of the molds 70 along their upper horizontal flight.

Slabs or cast metal lengths produced in accordance with my invention eliminate piping and voids and produce a high quality metal length. A spongy core is avoided, since the cast metal length is not bent or stretched during the forming operation, as accomplished by the unit B. Although the metal length will ordinarily be directly utilized, thus eliminating conventional rolling conditioning operations, it may be directly hot-rolled, as shown in FIGURE 2A, advantageously conserving and utilizing the heat of the casting operation without the necessity of re-heating. This illustrates the flexibility of the utilization of my procedure and operating system.

The arrangement or system of my invention is economical as to plant equipment and space. For example, the unit B and the associated mold conveying system may approximate a height of about ten feet. From a longitudinal standpoint, the system only requires about three or four feet of movement of the cast metal length or slab until it is ready for the stripping operation. The total apparatus layout shown in FIGURES l and 2 may have an overall length of about forty feet. The manner of handling the ladle A is such that the crane used for carrying it can be employed for other plant purposes while the ladle is in the feeding position of FIGURE 3 and molten metal is being supplied to the casting apparatus. The casting operation may continue by reason of the use of the tundish chamber even when the ladle A has been emptied, since another filled ladle can be immediately substituted and the supply of molten metal to the tundish chamber quickly re-initiated without disturbing the continuous forming of a length of cast metal or the slab.

The refractory material for the unit B may be of a conventional silica type. Refractory brick or tile members may be employed for lining the inside of the tundish chamber, but I prefer to utilize a unitary member or piece for the adjustable gate 40 and the swing gate 48. Various metals may be cast-formed in accordance with my invention, including ferrous metals and alloys and non-ferrous metals and alloys, such as aluminum, copper, brass, etc. The inert gas, such as argon, may be supplied at above atmospheric pressures of about 15 to 20 pounds per square inch. The inert gas introduced into the tundish chamber serves to prevent the entry of ambient gases or air when one ladle A is being replaced by another and the connector spout 30 is momentarily exposed at its upper end; it also serves to seal-off the slide joint between the connector spout 30 and the tundish. The molds 70 will ordinarily be of metal construction and may be copperjacketed or clad along their inner metal-receiving surfaces. Temperature-controlling cooling air sprays or jets may be applied to or along outer surface portions of the molds, for example, to the forward mold of FIGURE 3 that is projecting from the exit end of the mold chamber defined with the gate 40, and to other forward molds including those from which the slab is being stripped.

Although I have illustrated an exemplary employment of my invention, it will be apparent to those skilled in the art that the principles thereof can be embodied in other structures and arrangements, and that various changes may be made in the construction, utilization and adaptation of the invention by those skilled in the art without departing from its spirit and scope.

What I claim is:

1. Apparatus for handling and casting molten metal into a lengthwise-extending integral piece which comprises, a frame, a housing carried by said frame and defining a molten metal receiving chamber therein and an adjacent control chamber therein, means for feeding molten metal into said receiving chamber, a series of pivotally-interconnected molds carried by said frame for forward movement horizontally beneath said housing, a movable wall operatively-carried within said control chamber and cooperating with said interconnected molds to define a horizontal mold chamber, a feed orifice open downwardly from said receiving chamber for feeding molten metal into a back end of said mold chamber, means for controlling the temperature of said movable wall to cast molten metal within said mold chamber, means for continuously forwardly-advancing said interconnected molds with respect to said housing as molten metal increments are progressively cast within said mold chamber and for advancing a forward portion of the cast metal piece out of a forward end of said mold chamber, and means for stripping the forward portion of the cast metal piece from the interconnected advancing molds forwardly of said mold chamber.

2. Apparatus as defined in claim 1 wherein, a continuous loop-like track structure is carried by said frame and has a horizontal upper flight along which said interconnected molds move forwardly to define said mold chamber, and said track structure has a lower return flight provided with supplemental track means for retaining said interconnected molds thereon.

3. Apparatus as defined in claim 2 wherein stations are positioned along said lower flight for cleaning, coating and heating said interconnected molds up to a casting temperature.

4. Apparatus as defined in claim 1 wherein, means is carried by said housing for raising and lowering said movable wall within said control chamber and with respect to the molten metal in said mold chamber.

5. Apparatus as defined in claim 1 wherein, means is provided for supplying an inert gas along said receiving chamber to define a protective inert gas curtain between the feed orifice and said forwardly-advancing interconnected molds at a back end of said mold chamber to protect the molten metal from the ambient, atmosphere.

6. Apparatus as defined in claim 1 wherein, a continuous loop-like structure is carried by said frame and has a horizontal upper flight along which said interconnected molds move forwardly to define said mold chamber, said track structure has a lower return flight along which said interconnected molds are moved backwardly in a return path, said loop-like track structure has a forwardly-downwardly sloped portion of about 2 to 3 with respect to the horizontal plane of forward movement of the cast metal piece beyond said mold chamber, and guide means is positioned forwardly of said track structure on the horizontal plane for maintaining the cast metal piece on the horizontal plane as it is advanced along said sloped portion to progressively strip it from said advancing molds.

7. Apparatus as defined in claim 6 wherein said track structure has an abrupt turning angular portion forward- 1y beyond said sloped portion which is connected to said lower return flight.

8. Apparatus for handling and casting molten metal into a lengthwise-extending integral piece which comprises, a frame, a housing carried by said frame and defining a molten metal receiving chamber therein and an adjacent control chamber therein, means for feeding molten metal into said receiving chamber, a series of pivotally-interconnected molds carried by said frame for forward movement horizontally beneath said housing, a movable wall operatively-carried within said control chamber and cooperating with said interconnected molds to define a horizontal mold chamber, a feed orifice open downwardly from said receiving chamber for feeding molten metal into one end of said mold chamber, means for introducing an inert gas under pressure into said receiving chamber and into said control chamber to force contaminating gases out of the molten metal introduced into said receiving chamber and said mold chamber, means providing an inert gas curtain to seal-off molten metal being introduced through said feed orifice from the ambient atmosphere at the point of introduction of the molten metal to the one end of said mold chamber, means for initially supplying heat to said movable wall and for subsequently supplying cooling fluid to said movable wall to cast molten metal within said mold chamber, means for continuously forwardly-advancing said interconnected molds with respect to said housing as molten metal increments are progressively cast within said mold chamber and for advancing a forward portion of the cast metal piece out of the opposite end of said mold chamber, and means for stripping the forward portion of the metal piece from the interconnected advancing molds without bending it from the horizontal axis of its cast form.

9. Apparatus as defined in claim 8 wherein, a continuous loop-like track structure is carried by said frame and has a horizontal upper flight along which said interconnected molds move forwardly to define said mold chamber, said track structure has a lower return flight provided with supplemental track means for retaining said interconnected molds thereon, and stations are positioned along said lower flight for cleaning, coating and heating said interconnected molds up to a casting temperature.

10. A method of continuously forming and advancing a longitudinally-extending metal slab which comprises, charging molten metal into a tundish chamber while protecting it from the ambient atmosphere, progressively endwise-forwardly advancing a continuously-pivotally-connected series of open-top and open-end molds horizontally in an aligned endwise-abutting relation along and beneath the tundish chamber while progressively feeding the molten metal from the tundish chamber forwardly-downwardly through a feed orifice into progressively advancing molds, casting the molten metal within a horizontal mold chamber defined between a top closure positioned forwardly of the feed orifice and cooperating under-positioned advancing molds to form a length of slab on a horizontal plane therein, maintaining a spaced relation between the advancing molds and the feed orifice at a back end of the mold chamber to facilitate the advancing movement of the molds, maintaining an inert gas curtain about the spacing between the feed orifice and the advancing molds at the back end of the mold chamber to sealoff the molten metal from the ambient atmosphere, advancing the slab forwardly out of a front end of the mold chamber on the horizontal plane as it is formed therewithin by carrying it within the advancing molds and while progressively forming and adding increments to its length within the mold chamber, sealing-off the forward end of the chamber from the ambient atmosphere, and stripping the slab from the advancing molds forwardly of the mold chamber.

11. A method as defined in claim 10 which comprises, vertically-adjusting the top closure of the mold chamber with respect to the molten metal therein to control the thickness of the slab cast therein and to seal-off the forward end of the chamber during the movement of a slab forwardly out of the chamber.

12. A method as defined in claim 10 which comprises, progressively endwise-forwardly advancing the molds beyond the mold chamber, first at a slight angle to the horizontal plane of their initial advance from the mold chamber of about 2 to 3 while supporting a portion of the slab forwardly thereof on the horizontal plane to strip the slab from the advancing molds, and thereafter advancing the molds in an abrupt angular relation with respect to the horizontal plane along a return path of movement.

13. A method of continuously forming and advancing a longitudinally-extending metal slab which comprises, charging molten metal into a tundish chamber from a ladle without exposing the molten metal to the ambient atmosphere, maintaining an inert gas atmosphere within the tundish chamber, progressively endwise-forwardly advancing a continuously-connected series of open-top and open-end molds horizontally in an aligned endwise-abutting relation along and beneath the tundish chamber while progressively feeding the molten metal through a feed orifice from the tundish chamber into the progressively advancing molds, casting the molten metal within a horizontal mold chamber defined between a top closure positioned forwardly of the feed orifice and cooperating advancing molds to form a length of slab hori zontally therein, sealing-off spacing between the feed orifice and the advancing molds with an inert gas curtain, applying inert gas with sufficient pressure to force out contaminating gases with respect to the molten metal being introduced into the mold chamber, advancing the slab horizontally-forwardly out of the mold chamber as it is formed therewithin by carrying it within the advancing molds and while progressively forming and adding increments to its length within the chamber; and stripping the slab from the advancing molds forwardly of the mold chamber by continuing to move it horizontally-forwardly, while moving the carrying molds downwardly therefrom and back towards a cooperating mold-chamber-definingreturned position with respect to the top closure.

References Cited by the Examiner UNITED STATES PATENTS 494,659 4/1893 Very 2257.2 1,340,137 5/1920 Pfister 83-408 1,928,562 9/1933 Harbord et al. 22573 2,015,154 9/1935 Palm 2257.2 2,166,006 7/1939 Harbord et al. 2257.3 2,371,604 3/1945 Brennan 22572 2,713,705 7/1955 Lapin 22209 2,837,790 6/1958 Rozian 22--200.1 2,996,771 8/1961 Armond et al. 22572 3,163,897 1/1965 Sylvester 22209 FOREIGN PATENTS 283,408 3/1931 Italy.

I. SPENCER OVERHOLSER, Primary Examiner.

R. D. BALDWIN, Assistant Examiner. 

1. APPARATUS FOR HANDLING AND CASTING MOLTEN METAL INTO A LENGTHWISE-EXTENDING INTEGRAL PIECE WHICH COMPRISES, A FRAME, A HOUSING CARRIED BY SAID FRAME AND DEFINING A MOLTEN METAL RECEIVING CHAMBER THEREIN AND AN ADJACENT CONTROL CHAMBER THEREIN, MEANS FOR FEEDING MOLTEN METAL INTO SAID RECEIVING CHAMBER, A SERIES OF PIVOTALLY-INTERCONNECTED MOLDS CARRIED BY SAID FRAME FOR FORWARD MOVEMENT HORIZONTALLY BENEATH SAID HOUSING, A MOVABLE WALL OPERATIVELY-CARRIED WITHIN SAID CONTROL CHAMBER AND COOPERATING WITH SAID INTERCONNECTED MOLDS TO DEFINE A HORIZONTAL MOLD CHAMBER, A FEED ORIFICE OPEN DOWNWARDLY FROM SAID RECEIVING CHAMBER FOR FEEDING MOLTEN METAL INTO A BACK END OF SAID MOLD CHAMBER, MEANS FOR CONTROLLING THE TEMPERATURE OF SAID MOVABLE WALL TO CAST MOLTEN METAL WITHIN SAID MOLD CHAMBER, MEANS FOR CONTINUOUSLY FORWARDLY-ADVANCING SAID INTERCONNECTED MOLDS WITH RESPECT TO SAID HOUSING AS MOLTEN METAL INCREMENTS ARE PROGRESSIVELY CAST WITHIN SAID MOLD CHAMBER AND FOR ADVANCING A FORWARD PORTION OF THE CAST METAL PIECE OUT OF A FORWARD END OF SAID MOLD CHAMBER, AND MEANS FOR STRIPPING THE FORWARD PORTION OF THE CAST METAL PIECE FROM THE INTERCONNECTED ADVANCING MOLDS FORWARDLY OF SAID MOLD CHAMBER. 10.A METHOD OF CONTINUOUSLY FORMING AND ADVANCING A LONGITUDINALLY-EXTENDING METAL SLAB WHICH COMPRISES, CHARGING MOLTEN METAL INTO A TUNDISH CHAMBER WHILE ENDTECTING IT FROM THE AMBIENT ATMOSPHERE, PROGRESSIVELY ENDWISE-FORWARDLY ADVANCING A CONTINUOUSLY-PIVOTALLY-CONNECTED SERIES OF OPEN-TOP AND OPEN-END MOLDS HORIZONTALLY IN AN ALIGNED END-WISE-ABUTTING RELATION ALONG AND BENEATH 